[MPlayer-users] [AO_ALSA] Unable to set buffer time near: Invalid argument

[Raymond Yau]

2010/5/16 Reimar Döffinger <Reimar.Doeffinger at gmx.de>

> On Sun, May 16, 2010 at 01:21:10PM +0800, Raymond Yau wrote:
> > 2010/5/8 Raymond Yau <superquad.vortex2 at gmail.com>
> >
> > > >> On Sun, 2009-12-20 at 09:55 -0500, Robert Henney wrote:
> > >
> > > >* the latest svn appears to have an alsa issue when playing more than
> one
> > > *>* file on some particular files I have.  it's reproducible too.
> > > *>*
> > > *>* the audio will consistently fail to initialize for the second video
> file,
> > > *>* though if the files are reversed or played separately or -ao oss is
> used
> > > *>* then the problem does not occur.
> > > *>*
> > > *>* mplayer -ao alsa
> "[SpoonSubs]_Sketchbook_full_color's_02_[E80DF436].mkv" \
> > > *>*
>  "[SpoonSubs]_Sketchbook_full_color's_03_[FFE2F973].mkv"
> > > *>*
> > > *>* results in:
> > > *>*   Building audio filter chain for 44100Hz/2ch/s16le ->
> 0Hz/0ch/??...
> > > *>*   [AO_ALSA] Unable to set buffer time near: Invalid argument
> > > *>*   Failed to initialize audio driver 'alsa'
> > > *>*
> > > *>* the sample files are in http://rut.org/sketch/
> > > *
> > > >> Do you still get this error with the current git repo
> > > (git://repo.or.cz/mplayer-build.git)? I fixed some issues that could
> > >
> > > perhaps cause this, but as I can't reproduce your problem on my machine
> > > I don't know whether those were the ones you hit.
> > >
> > > [AO_ALSA] Unable to set buffer time near: Invalid argument
> >
> > http://thread.gmane.org/gmane.comp.video.mplayer.cvs/12760
> >
> > some PCI sound cards have special constraint on period size to fit the
> > period with in the DMA page  ( On x86  DMA page is 4K bytes )
>
>
> The driver is still broken IMO, if it needs a specific period size,
> set_buffer_time_near
> should set it to that, not fail.
>
>
No, the most common HDA driver require period size must be multiple of 128
bytes ( PCIE brust size) , you cannot exactly set buffer_size to 0.5 second
since the common sample rate is 44100/48000 (multiple of 3 or 9 )

You just get a buffer time near to 0.5 second

only those USB audio driver allow you to set buffer time to 0.5 second